Anaemia

Iron deficiency anaemia is the most common type of anaemia in the UK. It occurs when the body does not have enough iron to produce adequate levels of haemoglobin, the protein in red blood cells that carries oxygen to tissues throughout the body.

Common causes include insufficient dietary iron, blood loss (such as heavy periods or gastrointestinal bleeding) and poor iron absorption. Pregnancy also increases iron requirements significantly.

Symptoms often develop gradually and may include:

Persistent tiredness and lack of energy
Shortness of breath on exertion
Pale skin and brittle nails
Heart palpitations

Blood tests including haemoglobin, ferritin, serum iron, total iron-binding capacity and red cell indices help confirm the diagnosis and assess severity. Identifying the underlying cause is just as important as correcting the deficiency itself.

Causes of Anaemia

Iron deficiency anaemia develops when the body's iron stores become depleted. This can happen for several reasons:

Blood loss is the most common cause in adults:

Heavy menstrual periods (menorrhagia) are the most frequent cause in women of reproductive age
Gastrointestinal bleeding from conditions such as stomach ulcers, bowel polyps, inflammatory bowel disease or bowel cancer. This bleeding is often slow and may not be visible in the stool
Regular use of non-steroidal anti-inflammatory drugs (NSAIDs), which can cause stomach irritation and bleeding

Insufficient dietary intake:

A diet low in iron-rich foods such as red meat, pulses, dark leafy greens and fortified cereals
Vegan and vegetarian diets may be lower in easily absorbed (haem) iron, though plant-based iron sources can be sufficient with careful planning

Impaired absorption:

Coeliac disease, inflammatory bowel disease and previous gastric surgery can reduce the gut's ability to absorb iron

Pregnancy and breastfeeding increase iron demands significantly, making supplementation commonly necessary.

Tests that can help check this condition

Learn more on the official NHS page .

Medical review

Dr. Shahzaib Ahmad MBBS, BSc, MRCP, FRCA, FFICM

Clinical Supervisor - Vitall|GMC 7495062|Profile

Dr Shahzaib Ahmad is a Consultant in Intensive Care Medicine with subspecialty experience in cardiac critical care and neurocritical care. He has extensive experience managing complex acute and cardiovascular conditions in hospital intensive care settings. Dr Ahmad supports Vitall in reviewing health content for clinical accuracy and alignment with current medical practice.

Reviewed on 22/05/2026

Next review due 22/05/2027

Review focus: Blood biomarkers, laboratory testing methodology, and biochemical interpretation.

This content has been reviewed for medical and scientific accuracy but does not replace advice from a qualified healthcare professional.